46 results about "Superconducting quantum computing" patented technology

The invention provides a multi-bit control system and method based on superconducting quantum computing. The method comprises the following steps: outputing an initial quantum state and an initial microwave sequence as cross-frequency signals; controlling a built-in multi-bit gate according to the received cross-frequency signals, and outputting a quantum state to be measured; measuring the quantum state to be measured to obtain an inherent fidelity of the current multi-bit gate; and performing computing according to the inherent fidelity to generate an optimized microwave sequence, and performing feedback and optimization on the optimized microwave sequence to obtain a target multi-bit gate.

The invention discloses an extensible superconducting quantum bit structure which comprises a plurality of superconducting quantum bit lines, each superconducting quantum bit line comprises at least one Josephson junction structure, and each Josephson junction structure is a Josephson junction, or a plurality of Josephson junctions, or a combination of the Josephson junction and an auxiliary line;a capacitor and an inductor which are directly connected with the Josephson junction; a coupler circuit which is used for adjusting the coupling strength between the superconducting quantum bits connected with the coupler, and the coupling strength can be adjusted to be close to or equal to zero; an overline which is used for connecting the superconducting quantum bit line and the ground on the two sides of the coupler line; Wherein the number of the capacitors directly connected with the Josephson junction is multiple, and the superconducting quantum bits are coupled with other circuits through a branch structure formed by the plurality of capacitors. The structure has the advantages of high precision, high expansibility and low crosstalk, and the application of superconducting quantum calculation is promoted.

The invention discloses a superconducting quantum bit structure with adjustable adjacent bit coupling strength. The superconducting quantum bit line comprises a first superconducting quantum bit line,including a capacitor C1, an inductance (shown in the specification) and a Josephson junction (shown in the specification). The capacitor C1 is connected with the inductor C1 in series, and the capacitor C1 is connected with the inductor C1 in series. The capacitor C1 is connected with the inductor C1 in series. The inductor C1 is connected with the inductor C1 in series. The capacitor C1 and theinductor (1) are connected in series, and the capacitor C1 and the inductor (1) are connected in parallel after the capacitor C1 and the inductor (1) are connected in series. The capacitor C1 and theinductor (1) are connected in series. Two ends of each of the first end and the second end of each of the first end, the second end and the third end. The superconducting quantum bit line also comprises a second superconducting quantum bit line, including a capacitor C2, an inductance (shown in the specification) and a Josephson junction (shown in the specification). The capacitor C2 and the inductor C2 are connected in series, and the inductor C2, the capacitor C2 and the inductor C2 are connected in series. The capacitor C2, the inductor C2 and the inductor C2 are connected in series. Capacitor C2 and inductor (shown in the specification) which are connected in series are connected to the capacitor C2 and the inductor (shown in the specification) in parallel, and the capacitor C2 and the inductor (shown in the specification) are connected to the capacitor C2 and the inductor (shown in the specification) in series. The number of the terminals is two, and the number of the terminals is two. The superconducting quantum bit structure also comprises a coupling loop, including a Josephson junction Lk forming a loop, an inductance (shown in the description) and an inductance (shown inthe description) as well as inductance (shown in the description) wherein the formula (1) is shown in the specification, and the formula (2) is shown in the specification. One end of the Josephson junction Lk is connected between the capacitor C1 and the inductor (please see the formula in the specification), and the other end of the Josephson junction Lk is connected between the capacitor C1 andthe inductor (please see the formula in the specification). The other end of the capacitor C2 is connected between the capacitor C2 and the inductor (please see the formula in the specification). Theother end of the capacitor C2 is connected between the capacitor C2 and the inductor (please see the formula in the specification); Inductance (shown in the description) and inductance (shown in the description) as well as inductance (shown in the description) According to the structure, the fidelity of the double-quantum-bit CZ gate is further improved, so that the precision of quantum calculation is improved, the expansibility is high, and the application of superconducting quantum calculation is promoted.

The invention discloses a superconducting circuit structure, a superconducting quantum chip and a superconducting quantum computer, and relates to the field of quantum calculation. According to the specific implementation scheme, the superconducting circuit structure comprises at least three calculation quantum bits; the bus qubit is connected with the calculation qubits, and equivalent coupling is generated between any two calculation qubits connected through the bus qubit; the coupling quantum bit is arranged between the calculation quantum bit and the bus quantum bit, connects the calculation quantum bit with the bus quantum bit and is used for regulating and controlling the coupling strength between the calculation quantum bit and the bus quantum bit; coupling between any two calculation quantum bits can be achieved, then quantum gate operation between any two calculation quantum bits is achieved, and meanwhile crosstalk between the calculation quantum bits can be effectively restrained.

The invention discloses a high-fidelity superconducting circuit structure, a superconducting quantum chip and a superconducting quantum computer, and relates to the field of quantum computing. According to the specific implementation scheme, quantum bits are calculated; the coupling device is used for being coupled with the two calculation quantum bits; the connection assembly is arranged betweenthe calculation quantum bit and the coupling device and is used for carrying out coupling connection on the calculation quantum bit and the coupling device so as to realize a target quantum gate basedon the coupling device and the calculation quantum bit; wherein the calculation quantum bit and the detuning intensity of the coupling device are positive values. In this way, parasitic coupling between the calculation quantum bits is eliminated by selecting reasonable superconducting circuit parameters, and the fidelity of the target quantum gate is improved.

The invention discloses a superconducting circuit architecture comprising a plurality of coupling devices, a superconducting quantum chip and a superconducting quantum computer, and relates to the technical field of quantum computing. The circuit comprises a first quantum bit, a second quantum bit, a first coupling device and a second coupling device, the first coupling device is coupled with thefirst quantum bit and the second quantum bit through a first connecting piece; the second coupling device is coupled with the first quantum bit and the second quantum bit through a second connecting piece; and the frequencies of the first quantum bit and the second quantum bit are between the frequency of the first coupling device and the frequency of the second coupling device, and the nonlinearstrength of the first coupling device is opposite to the nonlinear strength of the second coupling device in sign. According to the technical scheme of the invention, parasitic coupling between quantum bits in the superconducting circuit can be eliminated, and the fidelity of a single-bit quantum gate and a two-bit quantum gate realized in the superconducting circuit is improved.

A compiler for a gate-based superconducting quantum computer compiles hybrid classical/quantum algorithms for quantum processing cells with different configurations. The compiler inputs the algorithm and outputs code in a target language executable by a quantum processing cell of a quantum processing system that can execute the algorithm. The compiler includes various functionality, such as: parsing, analyzing control flows, addressing, compressing, and translating. The compiler optimizes algorithms in various manners using the functionality. Some optimizations include addressing efficiently, compressing based on simulations, and translating for efficient execution of parametric functions. The compiler may function in the environment of a cloud quantum computing system. The cloud quantum computing system may receive algorithms from remote access nodes for execution on local classical and quantum computing systems.

The invention discloses an optimization method and device for calculating single-bit gate sequence by superconducting quantum, and a medium, and is used for solving the problems that the time span ofan input microwave pulse sequence is too long, quantum bit degradation is caused, and the uncertainty of a superconducting quantum calculation result is caused. The method comprises the following steps: determining a rotation operation corresponding to a single-bit gate sequence according to a preset rule; according to each rotation operation corresponding to the single-bit gate sequence, correspondingly rotating the initial state of the quantum bit to obtain a final state of the quantum bit; determining an equivalent rotation axis and an equivalent rotation angle corresponding to the single-bit gate sequence according to the quantum bit initial state and the quantum bit final state; and determining an optimized pulse sequence corresponding to the single-bit gate sequence according to theequivalent rotation axis and the equivalent rotation angle. According to the method, the time span of microwave pulse input corresponding to the single-bit gate sequence can be shortened, so that thesame quantum bit final state can be obtained on the premise that the decoherence degree of quantum bits is minimum, and the calculation accuracy is improved.

The invention discloses an extensible superconducting quantum bit structure which comprises a plurality of superconducting quantum bit lines, each superconducting quantum bit line comprises at least one Josephson junction structure, and each Josephson junction structure is a Josephson junction, or a plurality of Josephson junctions, or a combination of the Josephson junction and an auxiliary line;wherein the capacitor and the inductor are directly connected with the Josephson junction; a coupler circuit used for adjusting the coupling strength between the superconducting quantum bits connected with the coupler, and the coupling strength can be adjusted to be close to or equal to zero. The number of the capacitors directly connected with the Josephson junction is multiple, and the superconducting quantum bits are coupled with other circuits through a branch structure formed by the plurality of capacitors. The structure further improves the expansibility of the superconducting quantum bit structure on the basis of improving the precision of quantum calculation, and promotes the application of superconducting quantum calculation.

The invention relates to an easy-to-expand and high-fidelity superconducting quantum chip structure and an operation method. The superconducting quantum chip structure is characterized by comprising aplurality of adjustable couplers and a plurality of quantum bits; wherein the quantum bits and the adjustable couplers are arranged alternately, and the static frequency of the adjustable couplers, the adjacent quantum bits and the frequencies of the quantum bits adjacent to the same adjustable coupler are located in different frequency bands; each quantum bit is provided with an independent microwave driving line XY, wherein each adjustable coupler is provided with an independent magnetic flux bias line Z, and a single-bit gate, a two-bit gate or a multi-bit controlled phase gate is realizedby applying a driving signal to the microwave driving line XY or the magnetic flux bias line Z. The method can be widely applied to the field of superconducting quantum computing.

The invention discloses a large-area aluminum single crystal film and a preparation method and application thereof. The preparation method comprises the following steps: sequentially carrying out organic cleaning, RCA1 cleaning, RCA2 cleaning, piranha solution cleaning and HF cleaning on a Si (111) substrate to obtain a pretreated Si (111) substrate; and under a vacuum condition, placing the pretreated Si (111) substrate in a molecular beam epitaxy device for surface treatment, and growing an aluminum single crystal film on the surface of the Si (111) substrate by adopting a molecular beam epitaxy technology to obtain the large-area aluminum single crystal film. Compared with a Si substrate traditional technology, the Si (111)/Al single crystal film prepared through the method has the advantages that a large-area Al single crystal film is achieved, twin crystals do not exist, the content of C, H and O impurities on a Si/Al interface can be obviously reduced, the intrinsic quality factor of a resonator is improved to 106, and preparation of high-quality superconducting quantum bits or superconducting quantum computers is facilitated.

The invention discloses a long-life storage device and a long-service-life storage method for superconducting quantum bits. The three-dimensional ellipsoid radio frequency superconducting thin film cavity with high quality factor is adopted, and compared with a currently used rectangular cavity, the three-dimensional ellipsoid radio frequency superconducting thin film cavity has the advantages that the quality factor reaches up to 1010; the superconductive quantum bits are coupled with the superconductive cavity, and the decorrelation time of the superconductive quantum bits is prolonged to a hundred milliseconds to second order, so that obstacles are cleared for realizing control and measurement of the quantum bits and quantum storage; according to the method, the superconducting quantum bits with long service life can be obtained, and the device method have important significance for quantum calculation, quantum storage, quantum information, quantum communication and other aspects; the three-dimensional ellipsoid radio frequency superconducting thin film cavity is applied to superconducting quantum calculation for the first time, a mature superconducting cavity technology and emerging superconducting quantum calculation are combined, and the superconducting quantum calculation is further extrapolated forwards.

A system and method are disclosed for a superconducting traveling-wave parametric amplifier (TWPA) with improved control and performance. In a preferred embodiment, the amplifier comprises an integrated array of symmetric rf-SQUIDs in a transmission line structure. A device was fabricated using niobium superconducting integrated circuits, and confirmed predicted performance, with a maximum gain up to 17 dB and a bandwidth of 4 GHz. A similar device can be applied as a low-noise, low-dissipation microwave amplifier for output from a superconducting quantum computer, or as a preamplifier, switch, or frequency converter for a sensitive microwave receiver, or as an output amplifier for a frequency-multiplexed superconducting detector array.

The invention provides a quantum circuit and a control method thereof, a superconducting quantum chip and a superconducting quantum computer, and relates to the field of quantum computers, in particular to the technical field of superconducting quantum chips. The quantum circuit comprises a quantum bit and a reading resonant cavity, and the adjustable coupler is configured to be coupled with the quantum bit and the reading resonant cavity. When the quantum bit is initialized based on the reading resonant cavity, the modulation frequency of the adjustable coupler is configured to be equal to the difference between the frequency of the reading resonant cavity and the frequency of the quantum bit.

The invention provides a superconducting quantum calculation system and a quantum bit manipulation method. The system comprises a control circuit and a superconducting quantum chip, the superconducting quantum chip comprises at least two communication regions and a first central exchange region, and each communication region comprises a first suspension superconducting bit and at least one first superconducting bit; the first central exchange area comprises first suspended superconducting bits and is used for transmitting quantum operation among the superconducting bits in different communication areas; and the control circuit is used for controlling the coupling strength of the first suspension superconducting bit and the first superconducting bit. Therefore, by controlling the coupling strength between the first suspension superconducting bits and the first superconducting bits, a single communication region or a central exchange region can be isolated, so that sub-spaces are effectively segmented, and two-bit gate control between different communication regions can be transited through the central exchange region; therefore, various quantum control required by general quantum calculation can be realized on a large-scale superconducting quantum calculation chip.

The invention discloses a system architecture of a superconducting quantum computer and an information processing method. The system architecture comprises temperature-controllable low-temperature equipment, a superconducting quantum processor, a low-temperature electronic function unit, a room-temperature terminal and a low-temperature room-temperature communication link. The superconducting quantum processor is arranged in the low-temperature equipment and works in a first temperature interval of mK magnitude. The low-temperature electronic function unit is arranged in the low-temperature equipment and works in a second temperature interval, the minimum value of the second temperature interval is higher than the maximum value of the first temperature interval, or the maximum value of the second temperature interval is higher than the maximum value of the first temperature interval, and the second temperature interval is overlapped with the first temperature interval; and the low-temperature electronic function unit is used for providing a required signal for the work of the superconducting quantum processor. the room-temperature terminal is in a third temperature interval, and the maximum value of the second temperature interval is smaller than the minimum value of the third temperature interval; and the room-temperature terminal communicates with the low-temperature electronic function unit through the low-temperature and room-temperature communication link.

The invention discloses an on-chip non-reflective quantum amplifier with nonreciprocity. The on-chip quantum amplifier provided by the embodiment of the invention is a two-port on-chip device with an isolation function and an amplification function, is small in size and low in dissipation, and has nonreciprocity. According to the on-chip quantum amplifier provided by the embodiment of the invention, the input signal and the output signal are isolated, and the interference of signal reflection on the quantum chip is prevented. The on-chip quantum amplifier provided by the embodiment of the invention can be integrated with a superconducting circuit, plays an important role in high-fidelity measurement of quantum bits of a large-scale superconducting quantum computer, and is very beneficial to large-scale development of the superconducting quantum computer.

The invention provides a niobium-based planar multi-superconducting quantum bit which comprises a substrate and a metal niobium film arranged on the substrate. A superconducting circuit is etched on the surface of the metal niobium film, and one or more Josephson junctions are prepared. The invention also provides a preparation method and application thereof. According to the present invention, the planar multi-superconducting quantum bit with the niobium substrate as the substrate is successfully obtained, and the problems existing in the technology for preparing the superconducting quantum bit through the aluminum substrate are solved. Tests of Institute of Physics of Chinese Academy of Sciences show that the performance of the multi-quantum bit obtained by the process reaches the corresponding level in the world. The niobium-based planar multi-superconducting quantum bit can be further applied to the calculation and simulation of superconducting quantum calculation on scientific problems and a three-dimensional processing technology of superconducting quantum bits.

The invention discloses an on-chip non-reflective quantum amplifier with a strong isolation function. The on-chip quantum amplifier provided by the embodiment of the invention is a two-port on-chip device with a strong isolation function, a circulation function and an amplification function, is small in size and low in dissipation, and has nonreciprocity. According to the on-chip quantum amplifier with the strong isolation function, the gain bandwidth product of the amplifier is increased, the strong isolation function is achieved, meanwhile, an HEMT can be replaced, and the cost of a superconducting quantum computer and the cost of a test system of the superconducting quantum computer are greatly reduced. The on-chip quantum amplifier with the strong isolation function, provided by the embodiment of the invention, can be directly connected with the quantum chip, so that the quantum chip is protected from counteractive interference of a subsequent circuit. Based on the on-chip quantum amplifier provided by the embodiment of the invention, the superconducting quantum test system is simplified, the size of the superconducting quantum test system is remarkably reduced, and large-scale development of superconducting quantum computers is facilitated.